JPS5949411B2 - gas turbine control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas turbine control device that drives driven devices such as pumps, compressors, and generators at constant rotation speed using a single-shaft turbine. The present invention relates to a gas turbine control device that can be applied to a variable speed case where a gas turbine drives a vehicle.

Since it is desired that the gas turbine generate the maximum output mainly within the safe temperature limits of the turbine section, an output rating that fluctuates in response to changes in the compressor inlet air temperature T1, that is, an output rating with T1 bias, is determined. There are many cases.

In other words, when determining a T1 flat rating that is not related to the transition of T1, the output at maximum T1, when the temperature of the turbine section is the highest, becomes the rated output, and at low T1, the temperature of the turbine section decreases. , the gas turbine will be used with sufficient output generation capacity,
In other words, when T1 is low, the gas turbine is not used to its capacity limit, which is uneconomical. FIG. 1 illustrates the T1 bias rating, in which the horizontal axis is T1 and the vertical axis is output PS. Curve a is the continuous rated output curve, which is the upper limit of output that will not affect the expected life of the gas turbine even if it is used continuously, and curve b is the maximum output limit curve, which is about 10% higher than curve a, and is immediately dangerous. However, it affects the expected lifespan and is allowed to operate with certain usage time restrictions.

Curves A and b differ for each designed gas turbine, but when the slope is downward to the right, for example, for an increase of T1=10°C, the PS decreases by about 10%.

In such a gas turbine, free use is allowed in the output state below curve a, that is, region A, and in region B between curves a and b, if the operating state enters that region,
First, an alarm is issued, and a signal is sent to the control unit of the driven device or its load device to start automatic load reduction operation, and if the operating state still remains within region B for a certain period of time, the output of the gas star pin is on curve a or
If the load condition does not fall to a sufficiently low level, the gas turbine is shut off and stopped, and the curve a
To provide a concrete method for an automatic output level control device that does not cause the operating state to enter the C region above the .

This control device cancels the automatic operation restriction within the B area described above when the gas turbine and its driven equipment are used in emergencies, etc., and also stops the automatic shutoff function. Both the operation and the components are simple and economical to make possible, and the driven equipment also allows for a T1 flat rating.
Similarly, it is easy to do and can be done economically.

For example, in a stationary gas turbine used in an environment with little atmospheric pressure fluctuation, the output of the gas turbine is approximately determined by the fuel flow rate WF, and the curves a and b in Fig. 1 are similar to the fuel flow rate curves in Fig. 2. It can be replaced with a'' and B5.

Curve A5 in FIG. 2 is tentatively named continuous rated fuel flow rate WFR curve, and curve b' is tentatively named maximum limit fuel flow rate WFMX curve.

The difference in fuel flow rate shown by curve a'' and curve b'' will be referred to as X hereinafter. 4 Below, embodiments of the present invention will be described with reference to the drawings. In FIG. 3, a fuel flow d from an external device (not shown) is pressurized by a pump 1, flows into an inlet 2a of a flow metering valve device 2, and is controlled by a valve opening angle φ of a valve opening/closing shaft 3. The determined fuel flow rate WF passes through the currently opened shutoff valve 4 from the outlet 2b, and is finally injected into the combustion chamber 101 of the gas turbine 100 and combusted. Note that 102 is a compressor, 103 is a turbine, and 104 is a driven device such as a generator. Reference numeral 2c denotes a bypass valve that returns the difference between the discharge flow rate of the pump 1 and WF, that is, the residual fuel flow, to the inlet side of the pump 1.

Reference numeral 5 denotes a minimum value selector, and a freely rotatable output shaft 6 is axially connected to the valve opening/closing shaft 3, and a receiving plate portion 7 is provided.

Reference numeral 8 denotes a spring that applies a spring force to the output shaft 6 so as to always open the valve in the valve opening direction.

Reference numeral 9 denotes a deceleration lever for determining the deceleration fuel flow rate WDEC to prevent misfire when decelerating the gas turbine 100, but methods other than those shown may also be used.

10 is a speed control lever, 11 is an output upper limit lever, and 12 is an acceleration lever, all of which are signal input levers that are independently rotatable around an input lever shaft 13.

The valve opening angle φ, that is, the fuel flow rate WF is determined by the lowest one of the three signal input levers 10, 11, and 12. 20 is a speed governor, which includes a rotation detector 21, a rotation setting device 22,
Consists of speed governor calculator 23, signal angle position converter 24,
This is a known device that is connected to the speed regulating lever 10 via the connecting rod 25 and performs the speed regulating function of the gas turbine 100.

Reference numeral 30 denotes a rotation converter, which is composed of a rotation-hydraulic pressure converter 31 and a hydraulic car position converter 32, and is connected to the acceleration lever 12, and is used to restrict the acceleration fuel flow to prevent surges in the compressor 102 during sudden acceleration. In combination with the deceleration lever 9, this is a known device that performs a deceleration fuel limiting function to prevent misfires during sudden deceleration.

40 is an electric servo-type output upper limit setting device; 41 is an electric servo actuator; an actuator lever 44 that is rotationally driven by an electric motor 42 via a gear mechanism 43; and a gear mechanism 45.
The wiper 46 has a potentiometer 47 which is rotationally driven, and the output upper limit lever 1 is connected to the output upper limit lever 1 via a connecting rod 48.
1 positioning is performed.

50 is a constant voltage generator, 51 and 52 are resistive voltage division type low fuel flow rate signal transmitters made of non-temperature sensitive resistors that generate low fuel flow signal voltage EPP at point M, and 53, 54 and 55 are also non-temperature sensitive resistors. This is a resistive voltage division type high fuel flow signal transmitter made of a temperature sensitive resistor, and is designed to generate a high fuel flow signal voltage EPF at the N point.

56 and 57 are also resistive voltage divider type T1 signal transmitters;
Reference numeral 6 denotes a temperature-sensitive resistor for detecting T1, which is placed in the air flowing into the compressor 102 of the gas turbine 100, and 57 is a non-temperature-sensitive resistor, which generates the T1 signal voltage ETl at the zero point.

60 receives the Tl5 signal voltage ETl at the O point and outputs the upper limit output T.
T1 amplifier that generates and outputs 1 correction signal voltage ETB, 61
is a starting fuel integrator, 62 is an adder, and three input terminals 6
The input signals received from 2a, 62b, and 62c are added to output an upper limit output fuel signal E to the output terminal 62d.

63 is an electric servo amplifier, which has a positive input terminal 63a, a negative input terminal 63b, and an output terminal 63 electrically connected to the electric motor 42.
It has c.

70 is the normally open contact of the first starting fuel relay 84, 71 is its normally closed contact, 72 is the normally open contact of the second starting fuel relay 1.85, 73 is the normally open contact 7, 74 is the output upper limit change relay 98 It is a normally open contact.

80 is a start command device for the gas turbine, and a start switch 81
, a stop switch 82, a start command calculator 83, an excitation coil 96 of the first start fuel relay 84, an excitation coil 97 of the second start fuel relay 85, and other safety and other function devices not shown. It's more familiar.

14 is a proximity detector attached to the output upper limit lever 11, and the mutual relationship between the receiving plate part 7 and the output upper limit lever 11 is the second one.
When they approach each other within the fuel flow rate difference X explained in the figure, a proximity signal is transmitted.

90 is a proximity signal integrator, 91 is a load level determiner, 92 is an excitation coil of the output earth limit changing relay 98, 93 is an alarm transmitter, and 94 is a control for the shutoff valve 4. 95 is a load control device for the driven device 104 of the gas turbine 100.

Next, the operation of the above configuration will be explained.

Since the rotation setting device 22 of the governor 20 is set to 100% of the rated rotation, the governor lever 10 is at the maximum openable position WGM until the gas turbine rotation reaches 100%.
X, and it follows a steep downward thrust line near 100% rotation and performs speed regulating operation. If the rotation increases further, the WGMN remains at the lowest possible closing position WGMN. These are shown in FIG. 4 by curve WG. The acceleration fuel flow limit and deceleration fuel flow limit consisting of the acceleration lever 12 and the deceleration lever 9 of the rotary converter 301 are shown by the rotational speed related curves WACC and WDEC, respectively, to prevent compressor surge and combustion misfire of the gas turbine. ing. The output upper limit setting device 40 is activated over time in conjunction with the activation command device 80.

When the start switch 81 is actuated, the start command calculator 83 transmits an operation start signal to the gas turbine starter (not shown), the ignition plug system (not shown), and the shutoff valve controller 94. 1, the excitation coil 96 of the fuel relay 84 is excited, its normally open contact 70 is closed, and its normally closed contact 71 is opened. The low fuel flow rate signal voltage EPP at point M is applied to the input terminal 61a of the starting fuel integrator 61, and the starting fuel flow rate signal voltage EP, which increases over time, is applied to the output terminal 61b.
S is output, and the first input terminal 62a of the next adder 62
transmitted to.

Since there is no input to the other input terminals 62b and 62c of the adder 62, the voltage EPS is output as is to the output terminal 62d and transmitted to the positive input terminal 63a of the electric servo amplifier 63. The voltage of the wiper 46 of the potentiometer 47 and the signal voltage corresponding to the actuator lever 44 are applied to the negative input terminal 63b of the other electric servo amplifier 63, and the output of the output terminal 63c is Since it is connected to the electric motor 42 of
The output upper limit lever 11 is driven in the direction of increasing the fuel flow rate WF, and the rotation of the gas turbine 100 continues to increase. When the rotation of the gas turbine reaches a predetermined N1 rotation, the startup command calculator 83 receives a rotation signal from a rotation detection circuit (not shown) and activates the excitation coil 9 of the second startup fuel relay 85.
6 is energized and its normally open contacts R2 and r3 are closed. As a result, the high fuel flow signal voltage EPF at the N point is determined by the adder 62.
is applied to the input terminal 62b of the adder 62, and at the same time, the upper limit output T1 correction signal voltage ETB generated by the T1 amplifier 60 is also applied to the input terminal 62c. The summed signal voltage is output, and as a result, the output upper limit setting device 40 outputs a high fuel flow LW.
Set the output upper limit lever 11 to the SF position.

The gas turbine continues to accelerate, and when it reaches 100% rotation,
As mentioned above, the speed governor 20 enters the speed governing operation state, and the valve opening angle φ, which had been mainly determined by the output upper limit lever 11, is now determined by the speed governor lever 10, and the driven device at that time Since the load condition of 104 is normally quite low, the fuel flow rate WF is lower than WSF by at least the aforementioned X. Until the speed regulating operation state described above is entered, the output upper limit lever 11 is in contact with the receiving plate 7, so the proximity detector 14 is emitting a proximity signal, and the output is determined by the action of the load level determiner 91. Although the excitation coil 92 of the upper limit change relay 98 is energized and its normally open contact 74 is closed, it enters the regulating operation state and the fuel flow rate WFl)
'If the state is lower than WSF by more than X, the proximity detector 1
After the proximity signal No. 4 disappears and a predetermined time elapses due to the action of the proximity signal integrator 90, the load level determiner 91 releases the excitation of the excitation coil 92, and the normally open contact 74 becomes open.

For this purpose, the resistor 53,
Resistance values 54 and 55 are selected, and as a result, the output limit lever 11 moves to the WSMX position.

In this case, WSMX and WSF in Figure 4 are WF in Figure 2.
It is assumed that both MX and WFR match.
Figure 5 shows temporal changes in the various variables described above.

The operation of the output upper limit lever 11 is related to the passage of time, but if the load conditions during startup of the driven device 104 are determined, the time course 2 of the rotation increase is also determined, so the operation of the output upper limit lever 11 is determined. Can be related to rotational speed. The curve WS in FIG. 4 shows the operation of the output upper limit lever 11 obtained in this manner converted into the final fuel flow rate.

In Fig. 4, the actual fuel flow rate WF during 3 starts is E, f
, g, h, i, j, k. The following is devised as a modification of the above embodiment.

If the startup fuel integrator 61 of the output upper limit setting device 40 is not provided, the startup 3. shown in FIG. Changes in the fuel flow rate WF, etc. inside the engine are slightly different, as shown in Figure 6, but this allows for a more rapid temperature rise rate in the turbine section during startup, and enables faster startup. The pros and cons of this are evenly divided. 4
, and a first starting fuel relay 8 in the starting command device 80.
By removing the excitation coil 96 of 4, the first starting fuel relay 8
The excitation coil 97 of the second starting fuel relay 85 is connected to the excitation coil 96 of No. 4, the low fuel flow signal generators 51 and 52 shown at 51 and 52 are removed, and the contacts 70 and 71 and the starting fuel integrator 61 are connected. If it is also removed, even faster startup is possible, but the temperature rise in the turbine 103 is at the maximum allowable limit, and depending on the purpose,
It can also be made more desirable. FIG. 7 shows changes in the fuel flow rate WF, etc. during startup in this case. It will be readily understood that the modifications described herein constitute pertinent elements of the invention, but are not essential. The gas turbine 100 has completed the startup described above and is operating at a constant rotation speed.
In the case where T1 increases, for example, the temperature sensitive resistor 56
T1 signal voltage ETl at 0 point whether the electrical resistance value becomes large or not
decreases, and the upper limit output T which is the output from the T1 amplifier 60
1 correction signal voltage ETB decreases.

Therefore, the upper limit output fuel signal E output from the adder 62
decreases, and the output upper limit lever 11 is pulled down in accordance with the rise in T1. The relationship between T1 and the output upper limit lever 11 at this time is made to match WFMX shown by curve b'' in FIG. 2. Next, if the load on the driven device 104 increases during constant rotation operation, , the fuel flow rate WF is increased by the action of the speed governor 20 in order to maintain a constant rotation.When this increased fuel flow rate WF enters region B in FIG. A signal is generated and transmitted to the input terminal 91a of the next load level determiner 91 with a predetermined time delay due to the integration operation of the proximity signal integrator 90.The load level determiner 91 immediately outputs the signal. The signal is transmitted to the input terminal 93a of the alarm transmitter 93 through the terminal 91b to activate an alarm device (not shown), or is further transmitted to the input terminal 95a of the load control device 95 of the driven device 104 to perform a load reduction function. At the same time, since the load level determiner 91 is equipped with a timer device, it is activated and the first time elapsed is equal to the limit time allowed within area B in FIG. After the time elapses, the excitation coil 92 is excited, the normally open contact 74 is closed, the high fuel flow signal voltage EPF at the N point is lowered, and the earth limit output fuel signal E at the output terminal 62d of the adder 62 is lowered, so that the output The upper limit setting device 40 lowers the output upper limit lever 11 in the valve closing direction.The amount of this lowering is indicated by X in FIG. Converted to WF, WFR curve A5 in Figure 2
Therefore, the output level of the gas turbine 100 is forcibly lowered to curve a in FIG. Since the relative positional relationship between the proximity detector 14 and the receiving plate 7 is such that the proximity signal is still being transmitted, the alarm operation and load reduction operation of the load level determiner 91 are also continuing. If, by automatic operation by the load control device 95 or manual operation based on an alarm, the load reduction amount exceeds the amount that causes the fuel flow rate WF to be lower than the level X lower than the WFR curve a'' in FIG. When the second time of the timer device of the load level determiner 91 has elapsed, a signal is transmitted to the output terminal 91c and transmitted to the input terminal 94a of the cutoff valve controller 94, and the cutoff valve 4 is closed and the gas turbine 100 is closed. It is designed to stop.

Furthermore, the load level determiner 91 is designed to restore all functions when the input signal at the input terminal 91a disappears, so that the fuel flow rate WF reaches the WFR shown in FIG. 2 within the first time. If the fuel flow rate WF becomes less than or equal to curve A5, or if the fuel flow rate WF becomes less than WFR-X within the second time period, the proximity signal of the proximity detector 14 disappears, and the proximity signal integrator causes a delay of a certain period of time. With this, the output upper limit lever 11 is
It returns to the WFMX curve b' in the figure. The output upper limit lever 11 to which the proximity detector 14 is attached moves smoothly without vibration because the output upper limit setting device 40 is an electric servo actuator, whereas the proximity signal integrator 90 has another function. Since the receiving plate 7 is vibrating, the detection signal contains many vibration components, so this is integrated and converted into a smooth signal to stabilize the operation of the related system. It does not require a perfect integral action,
Approximately, it is enough to perform an integral function. Although the relays 84, 85, and 98 shown in FIG. 3 are of electromagnetic contact type, they may be of non-contact type.

Similarly, the flow metering valve device 2, the minimum value selector 5, the speed governor 2
It is not necessary for any of the rotary converters 30 and 30 to have a structure completely matching that shown in FIG. 3, and other known structures can be applied. In addition, when used in the emergency mentioned above, in order to cancel the automatic operation restriction operation in area B in Figure 1, insert the opening/closing contact at point U in Figure 3 and open it. However, the driving restriction operation may be dependent on the manual operation by the driving supervisor.

To stop the automatic cut-off/stop machine, insert an opening/closing contact at the V point and do the same as above. Also, T1 flat rating and T
In order to make it switchable with a bias rating of 1, the temperature sensitive resistor 56 may be replaced with an exhaust temperature sensitive resistor. In addition, for a permanent T1 flat rating, each signal generator 56
, 57, the amplifier 60 can be removed. Any of the above modification methods can be made by simple modifications and meet the initial objectives.

[Brief explanation of the drawing]

Figure 1, Figure 2, Figure 4 to Figure 7 are various characteristic diagrams, Figure 3
The figure is a block system diagram showing an example of a gas turbine control device according to the present invention.

Claims (1)

[Claims] 1 A pressurized fuel supply source 1 that supplies fuel under pressure to a gas turbine, a flow rate control valve mechanism 2 for supplying fuel to the gas turbine, and a governor 20 that maintains the rotation of the gas turbine at a commanded constant rotation. , an output level discriminator 91 that determines whether the output level of the gas turbine is in the upper or lower region of the continuous rated output curve, a maximum fuel flow signal generator 51 that commands the upper limit value of the fuel flow at the rated rotation, and a compression Machine 1
A correction signal generator 5 detects the inlet air temperature T_1 of 02 and generates a temperature correction signal to be added to the maximum fuel flow signal.
6, 57, 60, an adder 62 that adds the output signals from both signal generators, and an output upper limit to which the output of the adder 62 is applied to set the position of the output upper limit lever 11 of the minimum value selector 5. Lever operating mechanisms 41 and 63; a detector 14 that detects the limit position of the output upper limit lever 11 that rotates when the fuel flow rate increases above the continuous rated output curve and transmits a constant load increase signal to the output level discriminator 91; , an alarm transmitter 93 that receives a signal from the output level discriminator 91 in an output region exceeding the continuous rated output curve and issues a load increase alarm;
Load reduction transmitting means for receiving a signal from the output level half divider 91 in the output region exceeding the continuous rated output curve and transmitting a signal to lower the load on the turret pin that increases at the rated rotation; It is characterized by comprising a control circuit that lowers the upper limit output fuel signal E from the adder 62 after a certain period of time has elapsed from the time when the continuous rated output curve is exceeded, and controls the output upper limit lever 11 in the valve closing direction. Gas turbine control device.